1. Field of the Invention
The present invention relates to a wireless communication system, more particularly to a wireless communication system having a synchronizing unit.
2. Description of the Related Art
The global positioning system (GPS) utilizes direct sequence spread spectrum (DSSS) techniques for transmitting GPS signals, each of which contains information of a corresponding one of the GPS satellites. To obtain the information of a GPS satellite, a GPS receiver receives GPS signals transmitted by the GPS satellite, and includes a synchronizing unit for determining from the GPS signals a matching carrier signal and a matching phase of a corresponding pseudo-noise (PN) sequence signal so as to demodulate the GPS signals.
Assuming a conventional GPS receiver receives GPS signals of a number (V) of GPS satellites, and is operable to generate a number (F) of candidate carrier signals, the conventional GPS receiver is required to perform (V×F) cross-correlation computations just to determine the matching carrier signals, which can be time-consuming and inefficient. Furthermore, the conventional GPS receiver requires a large buffer unit for buffering the GPS signals, which can increase the hardware cost.